For some electrical power distribution systems, balancing power generation with energy demands (i.e., load) can be challenging, particularly when the electrical power distribution systems are connected to electrical power generating systems having a variable power output, such as wind power generators and solar power generators. For instance, wind power generators generate electrical energy outputs that vary widely depending on the wind speeds. Additionally, the power generated by such systems cannot be easily controlled by adding or removing wind turbines responsive to the energy load on the system.
As a result, variable output power generators often generate electrical energy that exceeds the demand on the electrical power distribution systems, such as during high wind conditions at off-peak power demand times. Such excess energy may be wasted if the load on the electrical power distribution system is not adjusted.
For many years electrical power distribution systems have controlled energy consuming devices through a communication that turns the devices on or off. Typically, this control is used to reduce the power demand on electrical power distribution system peak power consumption periods, as described in U.S. Pat. No. 8,010,240. U.S. Pat. No. 8,121,742 discloses an energy distribution system that controls the activation and deactivation of a group of water heaters for the purpose of controlling the load on the grid. This activation and deactivation of groups of electrical devices by the electrical power distribution system is conducted without actual knowledge of how it may affect the energy demands placed on the electrical power distribution system. Accordingly, control of the actual energy demand using these techniques is limited.
U.S. Pat. No. 8,805,597, which issued to Steffes Corporation, discloses a technique for controlling a rate of energy consumption by electrical appliances responsive to a signal from the electrical power distribution system. This allows the electrical power distribution system to adjust the energy consumption of electrical appliances to meet its needs.